Why a Successful Ping Does Not Mean Your Network or App Is Working Fine

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A common misconception in network troubleshooting is assuming a successful ping confirms full connectivity, but ping only tests ICMP echo requests — a narrow slice of what applications actually need. An HTTPS connection requires multiple additional layers to succeed, including DNS resolution, a TCP connection to port 443, a TLS handshake, and a valid HTTP response from the server. Each of these layers can fail independently, meaning a firewall could block TCP traffic while still allowing ICMP, or TLS could fail even after DNS and TCP succeed. Diagnostic tools like dig, netcat, openssl s_client, and curl with verbose output allow engineers to isolate exactly which layer has broken down. Pinpointing the failure layer — network, DNS, TCP, TLS, or application — leads to faster, more accurate troubleshooting than relying on ping alone.

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AWS Lambda timeout raised 6x to 90 minutes for managed instance event-driven functions

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ProgrammingDEV Community ·

Why Regulated AI Apps Need More Than a Vector Database

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ProgrammingDEV Community ·

Fix Ollama Connection Errors in MuleSoft by Using host.docker.internal

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ProgrammingDEV Community ·

How a Successful Build Left Almost No Trace in the Permanent Record

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